Fluorescent lamp socket



Nov. 19, 1963 e. A. NELSON FLUORESCENT LAMP SOCKET Filed June 5, 1961INVENTOR 6252222 AJVZson l BY @M-JQM- ATTORNEYS United States PatentOfiice 3,111,353 Patented Nov. 19, 1963 3,111,353 FLUQRESCENT LAMPSGCKET Glenn A. Neison, Stockton, Caliii, assignor to Electric Lighting,Inc, tockton, Calii, a corporation of California Filed June 5, 1961,Ser. No. 114,950 3 Claims. (Cl. 339-il) This invention relates tosockets for the ends of fluorescent light tubes or lamps, andparticularly to sockets designed for outdoor use, where they are exposedto the elements.

A major object of the invention is to provide a socket for the purposeso constructed that all moisture and dampness is prevented from passingbetween the lamp end and the socket, and which would settle on the barecurrent-carrying contacts of the lamp and socket.

Another object of the invention is to construct the socket so that thereis positive electrical contact between the lamp and ballast leads, andwhich socket has no springs-included in the current carrying partswhichwould tend to cause voltage drop.

A further object of the invention is to construct sockets which willsupport fluorescent tubes and withstand severe vibration without arcingbetween the socket and lamp contacts.

lt is also an object of the invention to provide a fluorescent lampsocket which is designed for ease and economy of manufacture.

An additional object of the invention is to provide a practical andreliable fluorescent lamp socket, and one which will be exceedinglyeffective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relativearrangement of parts as will fully appear by a perusal of the followingspecification and claims.

In the drawings:

FIG. 1 is a foreshortened elevation of a conventional fluorescent lighttube or lamp as mounted in the new sockets, and with the latter mountedin their supports; said supports being shown in section.

FIG. 2 is an enlarged sectional elevation of one of the sockets, and theadjacent lamp end engaged therewith.

FIG. 3 is a cross section on line 33 of FIG. 2.

FIG. 4 is a similar view on line 44 of FIG. 3.

Referring now more particularly to the drawings, and to the charactersof reference marked thereon, the fluorescent light tube or lamp 1 is ofa conventional and standard type, and includes end heads or bases 2adapted to be connected to and supported by the special sockets 3, whichare described in detail hereinafter.

Each base 2 is formed with a relatively small sized extension or neck 4which is of generally oval form in section, as shown in FIG. 3; the neckhaving an opening 5 therethrough symmetrical to the neck, orin otherwordsof elongated oval form.

Contact strips 6 for the lamp electrodes extend lengthwise of theopening 5, parallel to the lamp and neck, at the top and bottom, or atthe widest part, of said opening in facing relation to each other. Thisis standard lampbase construction, and I do not alter the same in anyway.

The sockets 3 are designed to cooperate with the lamp bases and contacts6 therein, and since the two sockets are of identical construction, adescription of one will sufiice for both.

Each socket comprises a body 7 of dielectric material having an enlargedflange 8 at its forward lamp-facing end. The body at said end is formedwith a central cavity 9 symmetrical to and only slightly larger than thebase extension 4 to receive the same in substantially non-turnablerelation. The body 7 at said end is also formed with a circular annulargroove 10 located between the cavity 9 and the periphery of the flange8.

A rubber or similar sealing ring 1 1 of any suitable cross sectionalform is seated in the groove and projects from said end of the body toengage the adjacent face of the lamp base 2 when the base neck 4 isinserted for substantially its full extent into cavity 9, as shown inFIG. 2. A water or moisture tight seal is thus made between the interiorof the socket and the lamp base.

A relatively large chamber 12 in the socket body opens to the rear endof the same; the chamber and cavity 9 being separated by a transversewall 13. Projecting forwardly from chamber 12 into cavity 9 centrallythereof through an opening 14 in wall 13 is a core 15, also ofdielectric material. This core is an elongated member of rectangularform in section and when the neck 4 of the lamp base 2 is projected intothe cavity 9, the core then extends some distance into the opening 5 ofsaid neck. The core from its forward end 16 to a point relatively closeto its rear end is slit to provide a longitudinal slot 17, the opposedWalls of which are parallel to the contacts 6.

At the rear end of the slot a mounting pin 18, parallel to the walls ofslot 17, projects through the core and is supported in the walls of thebody 7 to the sides of chamber 12; said walls having pin-surroundingsleeves 19 which extend to the opposite sides of the core 15, as shownin FIG. 4, and which prevent lateral shifting of the core.

The forward portions of the opposed faces of the core which are parallelto the walls of slot 17 are longitudinally grooved, as at 2%, to seatcontact strips 21 which project from said core faces to slidably engagethe lamp base contacts 6 when the base neck is engaged in the socket, asshown in FIG. 2. The contact strips 21 at their forward ends are formedwith rounded tips 22 projecting toward each other and into recesses 23in the core.

The core and contact strips are proportioned relative to the neckopening 5 so that when unrestrained, the direct distance between thecontact strips 21 at their forward ends is slightly greater than thedirect distance between the base contacts 6. As a result, when the neck4 is inserted into the socket cavity 9 and over the core, thecooperating contacts 21 and 6 become firmly and frictionally engagedwith each other, the resilient core yielding to the extent necessary assuch engagement is effected.

The contact strips 21 terminate in chamber 12 just back of the wall :13,where they are connected to or integral with wider strips #24. Thesestrips 24 first extend away from each other in adjacent and parallelrelation to the wall 13 for some distance, and are then bent, as at 25,to extend toward the rear end of chamber 12, but terminate well short ofsuch end.

The strip portions are formed with clamping sleeves 2.6 for the exposedends of the current conducting wires 27. These wires may extend in anydirection from the chamber 12, but in the event that the socket abuts atits rear end against a flat surface, the wires are deflected in oppositedirections through recesses 28 in the rim of the chamber.

The core within the chamber 12 is preferably formed with opposed pairsof fins or vanes 29 which extend from the rear end of the core to andsubstantially abutting against the contact strip portions 24 and thuspreventing any pull on Wires 27 from deforming said strip portions. Atthe same time, the vanes terminate, in a radial direction short of thestrip portions 25 so as not to interfere with the wire connectingoperations. The vanes of each pair are spaced apart in parallelrelation, the spacing being the same as the width of the core grooves20.

It should here be noted that after all the parts of the socket have beenassembled, the rear end portion of the chamber is substantially filledand closed with a mastic sealant of suitable type.

Each socket is supported from an end plate 31 of the lamp housing 31,the socket body 7 projecting through a symmetrical fitting opening 32 inthe plate 34 the enlarged end flange 8 being in front of the plate andincapable of passing through the opening 31. One socket is disposed withits flange 8 against plate 38, being removably held in such position bya spring keeper 33 behind the plate and engaged in opposed grooves 34 inthe socket body 7.

The other socket is engaged by a helical compression spring 35 extendingbetween the flange S of such socket and the front face of the adjacentplate 3i), so that said socket is yieldably pressed against the adjacentlamp base. Escape of this socket from the plate 3% is prevented by akeeper 33a which then engages other opposed grooves 36 the socket bodyadjacent its rear end; said grooves being disposed in a plane at rightangles to the wire recesses 23 so that the keeper does not interferewith the wires.

By reason of the above described features of construction andarrangement of pants I have provided the only fluorescent recesseddouble-contact lamp socket which, to my knowledge, meets UL outdoor-usestandards.

From the foregoing description it will be readily seen that there hasbeen produced such a device as will substantially fulfill the objects ofthe invention, as set forth herein.

While this specification sets forth the present and preferredconstruction of the device, still in practice such deviations from suchdetail may be resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described the invention the following is claimed as new anduseful and upon which Letters Patent are desired:

1. A socket for cooperation with a fluorescent lamp base, the basecomprising a main member having a reduced size neck projecting outwardlyof the lamp therefrom, said neck having an opening therein extending tothe outer end thereof, and opposed contacts in the neck exposed Withinthe opening; the socket including a body having a cavity open to theforward end of the body to receive the neck in substantiallynon-turnable relation, a core mounted in the socket position to projectinto the neck opening when the neck is in the cavity, opposed contactssupported on the core then engaging the neck contacts, extensions on therear ends of said last named contacts projecting radially out therefromand terminating in longitudinally extending rear-end portions within llthe socket, wire clamps on the rear ends of such portions, and meansremovably mounting the core in the socket for withdrawal therefrom as aunit with the last named cont-acts and extensions.

2. A socket, as in claim 1, in which the last named contacts at theirforward ends are formed with tips turned toward and seated in recessesin the core.

3. A socket for cooperation with a fluorescent lamp base, the basecomprising a main member having a reduced size neck projecting outwardlyof the lamp therefrom, said neck havin an opening therein extending tothe outer end thereof, and opposed longitudinally extending contactstrips in the neck exposed in the opening and extending lengthwise ofand parallel to the axis of the base; the socket comprising a bodyhaving a cavity open to the forward end of the body to receive the neckupon relative longitudinal movement of the base and socket, a coremounted in the body and extending lengthwise thereof and into the cavityin position to project into the neck opening when the neck is moved intothe cavity, longitudinally extending opposed contact strips supported onthe core slidaoly engaging the neck strips, a transverse partition wallin the socket at the rear end of th cavity through which the core andlast named contact strips project with a sliding fit, and providing achamber in the socket rearwardly of the wall, extensions projectingrear-wardly from said last named contact strips and adapted at theirrear ends for connection to currentcarrying wires; the extensionsincluding forward-end portions projecting radially out from the coreimmediately back of said wall, and opposed vanes on and projectingradially out from the core rearwardly of said forward end portions ofthe extensions and confining the same between the wall and vanes.

References Cited in the file of this patent UNITED STATES PATENTS2,296,114 Mueller et al. Sept. 15, 1942 2,475,243 Irrgang July 5, 19492,715,216 Howenstine Aug. 9, 1955 2,746,620 Pistey Apr. 17, 19562,781,497 Sheskier c Feb. 12, 1957 2,793,354 Heimbach May 21, 19572,919,420 Snodgrass et al. Dec. 29, 1959 3,005,175 Pistey Oct. 17, 1961FOREIGN PATENTS 961,275 Germany Apr. 4, 1957 1,063,643 France Dec. 16,1953

1. A SOCKET FOR COOPERATION WITH A FLOURESCENT LAMP BASE, THE BASECOMPRISING A MAIN MEMBER HAVING A REDUCED SIZE NECK PROJECTING OUTWARDLYOF THE LAMP THEREFROM, SAID NECK HAVING AN OPENING THEREIN EXTENDING TOTHE OUTER END THEREOF, AND OPPOSED CONTACTS IN THE NECK EXPOSED WITHINTHE OPENING; THE SOCKET INCLUDING A BODY HAVING A CAVITY OPEN TO THEFORWARD END OF THE BODY TO RECEIVE THE NECK IN SUBSTANTIALLYNON-TURNABLE RELATION, A CORE MOUNTED IN THE SOCKET IN POSITION TOPROJECT INTO THE NECK OPENING WHEN THE NECK IS IN THE CAVITY, OPPOSEDCONTACTS SUPPORTED ON THE CORE THEN ENGAGING THE NECK CONTACTS,EXTENSIONS ON THE REAR ENDS OF SAID LAST NAMED CONTACTS PROJECTINGRADIALLY OUT THEREFROM AND TERMINATING IN LONGITUDINALLY EXTENDINGREAR-END PORTIONS WITHIN THE SOCKET, WIRE CLAMPS ON THE REAR ENDS OFSUCH PORTIONS, AND MEANS REMOVABLY MOUNTING THE CORE IN THE SOCKET FORWITHDRAWAL THEREFROM AS A UNIT WITH THE LAST NAMED CONTACTS ANDEXTENSIONS.